Portable slow descender

ABSTRACT

The slow-descending device of this invention is so small and light that anybody can easily carry it in a traveling bag, or the like. Therefore, it is useful as an emergency evacuation device which enables him to escape from a fire in a hotel, apartment house, office building, etc., or from a disaster in a high level road or highway, etc.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to a device used for the evacuation from a highbuilding in cases such as a fire, particularly to a slow-descendingdevice for evacuation which enables a person to descend safely from ahigh place, and more particularly to a portable slow-descending devicefor evacuation which anybody can carry for personal use.

2. Related Art

Although a building or other type of structure usually equipped withevacuation devices, they are not provided in every room, but areprovided only in a particular room or rooms, or at a particular site orsites of a corridor or corridors. In the case of an emergency such as afire, therefore, it is very likely that many people may rush to eachevacuation device and cause a panic, or it is even likely that fire orsmoke may prevent people from reaching to any of the places where thosedevices are provided, and to use them. An evacuation device having alifeline formed from a metal wire is heavy and unsuitable for portableuse. Moreover, it has a limit in the distance along which it enables aperson to descend, i.e. the height of the story from which it enablesthe person to descend. Its use is limited to a low building having aheight of, say, 30 m at a maximum. There is every likelihood that aperson using it to escape from a high building may be suspended in theair. Thus, it has only a limited scope of use. There has also beenproposed a device which includes a wire having a smaller diameter and alonger length. However, it is not only heavy, but is also liable torusting by salt or moisture. Therefore, it is unsuitable as a device ofthe kind under consideration which is required to be semipermanentlyuseful without undergoing any substantial change in quality.

There has also been proposed a device which includes a lightweight ropeformed from a non-metallic material. It is, however, likely that when aload has acted upon the rope extending down from e.g. a reel on which itis wound, it may be deformed and caught between coils thereof on thereel, resulting in the failure of the rope to be smoothly unwound andthe failure of the reel to turn smoothly, and that a person who is beingrescued may, therefore, be suspended in the air.

There are known various types of mechanisms for slow-descending devices.A device employing a hydraulic system is likely to have a greatlyvarying descending speed which may depend on the weight of a person whois rescued. When it is used in a very cold place, however oil is likelyto solidify. Moreover, a change in quality of oil or its leakage islikely to occur.

It is an object of this invention to provide a portable slow-descendingdevice which can overcome the drawbacks of the devices describedhereinabove.

SUMMARY OF THE INVENTION

The portable slow-descending device of this invention comprises alifeline in the form of a tape made of synthetic or chemical fibers, ahook attached to one end of the lifeline, a reel on which the lifelineis wound a frame for supporting a reel supporting shaft rotatably atboth ends thereof, a suspending ring connected to the frame and adaptedfor connecting the device to a person using it, a planetary gearacceleration unit embedded in the reel, and a centrifugal brakemechanism linked to the planetary gear acceleration unit.

The lifeline is preferably made of aramid fibers.

The device preferably also includes a manual control member which canselectively lock the centrifugal brake mechanism.

Moreover, the device preferably includes a manual member for rewindingthe lifeline on the reel.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view showing the major part of a portableslow-descending device embodying this invention;

FIG. 2 a schematic view showing a centrifugal brake mechanism and amanual control member therefor;

FIG. 3 is a schematic view showing a planetary gear acceleration unit;and

FIG. 4 is a cross-sectional view of the portable slow descender.

DESCRIPTION OF PREFERRED EMBODIMENTS

A device embodying this invention is generally shown in FIG. 1. Itincludes a lifeline 1 in the form of a tape made of synthetic orchemical fibers, and wound superposedly on a reel 2. The lifeline 1 hasone end not shown, but provided with an appropriately shaped hook whichis used for fastening the lifeline 1 to an appropriate part of abuilding. The reel 2 is supported on a shaft 18 which is rotatablysupported on a supporting frame 3 at both ends thereof. A centrifugalbrake mechanism which is schematically shown in FIG. 2, and a planetarygear acceleration unit which is schematically shown in FIG. 3 arejuxtaposed to each other in the interior of the reel 2 and separated bywall 40 as shown in FIG. 4. The planetary gear acceleration unitcomprises three equally spaced apart planetary pinions 4 rotating aboutshafts 30, a sun gear 5 meshing with the pinions 4, and a large planetgear 12 secured to the reel 2 and meshing with the pinions 4. Thecentrifugal brake mechanism includes a centrifugal weight 6 whichsurrounds shaft 18 of the sun gear 5 and rotates with rotation of thesun gear 5. The centrifugal weight which is schematically shown in FIG.2 is of the type substantially semilunar members 6,6 which are fixed atpoints 34 and to a shoe holder 38 integrally connected to the shaft 18as is sun gear 5 and normally urged radially inwardly toward each otherby springs 14 against an inner periphery 36 of reel 2. It is, however,possible to use any other type of centrifugal weight known in the art,too. The centrifugal brake mechanism further includes a cam 16 providedin its center, a manual brake arm 7 connected to the cam, and a knob 8connected to the arm 7. A suspending ring 9 is connected to the frame 3,but may be replaced by a life jacket or any other similar device. Theshaft 18 on which the sun gear 5 is supported has one end provided witha recess 20 into which a handle 10 having corresponding protrusion 22for rewinding the tape can be connected.

FIG. 4 is a cross-sectional view showing details of the relationshipbetween the centrifugal brake chamber of FIG. 2 and the planetary gearchamber of FIG. 3.

The lifeline 1 in the form of a tape is preferably formed from syntheticor chemical fibers, such as aramid fibers (Kepler). The lifeline formedfrom these materials is light in weight, strong, has a high degree ofheat resistance (capable of withstanding a temperature of about 450°C.), and does not form rust. Therefore, it is semipermanently useful. Asit is a tape, it is unlikely to get caught between its own coils on thereel, as opposed to a rope, and can, therefore,

have a length which is as long as about 100 m. It is very long, ascompared with the conventionally employed ropes having a length of onlyabout 30 to 40 m. The tape also has the effect of preventing theswiveling of the device.

If a manual control member is provided for locking the centrifugal brakemechanism selectively, it is possible to control the descending speed ofthe device. It is also possible to stop the device at any desiredposition during its descent and it is, therefore, possible, for example,for a person descending from a 20-story or higher building to stop at alower story and escape into the same building.

If a manual tape rewinding member is provided, the device is easier tomake ready for reuse.

I claim:
 1. A portable slow-descending device comprising:a lifeline inthe form of a tape made of a synthetic material; a reel on which saidlife line is wound in superposing layers, said reel including a cylinderand opposing rims; a frame for rotatably supporting a shaft of said reelat both ends of the shaft; a suspension ring connected to said frame andadapted for connecting the device to a person; a planetary gearacceleration unit formed within said cylinder; and a centrifugal brakemechanism linked to said planetary gear acceleration unit within saidcylinder and separated therefrom by a wall member, wherein said devicedescends with the person connected thereto for enabling access tomechanical parts during descent.
 2. A portable slow descending device asset forth in claim 1, wherein said synthetic material is made of aramidfibers.
 3. A portable slow-descending device as set forth in claim 1,further including a manual control member integrally connected with saidreel supporting shaft for selectively locking said centrifugal brakemechanism during descent of said portable slow-descending device.
 4. Aportable slow-descending device as set forth in claim 1, furtherincluding a manual member for rewinding said lifeline on said reel.
 5. Aportable slow-descending device comprising:a lifeline in the form of atape made of synthetic fibers; a reel for receiving said lifeline inrepetitively wound superimposed layers, said reel including a cylinderportion and a pair of rim members, each rim of said pair being formed atopposing ends of the cylinder; a rotatable shaft axially formed throughthe cylinder of said reel; a frame member for rotagably supportingopposing ends of said rotatable shaft; a planetary gear accelerationunit formed within the cylinder portion of said reel; a centrifugalbrake mechanism operatively connected to said planetary gearacceleration unit within the cylinder portion of said reel and separatedtherefrom by a wall member; and a manual control member connected tosaid centrifugal brake mechanism for selectively controlling descent ofsaid device, wherein said device descends with a person connectedthereto, thereby enabling constant access to said manual control memberduring descent.
 6. A portable slow-descending device as set forth inclaim 5, wherein said lifeline is made of aramid fibers.
 7. A portableslow-descending device as set forth in claim 5, further including amanual member for rewinding said lifeline on said reel.